Vegetable oil can be used as an alternative fuel because it can reduce exhaust emissions are more environmentally friendly than high a fc viscosity material and low heating value. Therefore it is necessary efforts to improve the nature of fatty acid characteristics. One of them is to do the vegetable oil with heating. Raw materials of vegetable oil that have potential as fuel include palm oil and corn oil. The research mix of palm oil and corn oil is done by variation of composition and variation of mixing time. Comparison of mixed variation composition was 100: 0, 90:10. 80:20, 70:30, 60:40. 50:50. 40:60. 30:70, 20:80, 10:90 and 0: 100 (%). Duration of mixing accompanied by heating done for 30 minutes and addition of 60 and 90 minutes of mixed special 50:50 (%) for research mixing time variation. Based on the test results, the more percentage variation of the mixture composition of corn oil and the longer variation mixing time with heating affect the physical properties . The more variation of corn oil mixture composition in palm oil, the viscosity, flash point decrease and the density and the calorific value increase. While in testing the mixing time variation, the longer the mixing time mixed with the heating, the value of density, viscosity, fiash point increase and the calorific value decreases.